Repair manual

3.2.9 Switch-off upon Failure
The control unit recognises failures of individual air
heater components and malfunctions in the start se-
quence and in normal operation.
The air heater is deactivated and enters the error loc-
kout mode under the following conditions:
flame sensor open or short circuit
temperature sensor open or short circuit
glow plug open or short circuit
fan motor open or short circuit or fan speed wrong
dosing pump open or short circuit
overheating
low voltage below 10 Volt or high voltage above
15 Volt in excess of 20 seconds for 12 Volt heaters
low voltage below 20 Volt or high voltage above
30 Volt in excess of 20 seconds for 24 Volt heaters
A switch-off like in “switch-off” will be performed.
In case of overheating there will be no fuel supply. After
run-down the control unit is in the error lockout mode.
The operation indication outputs a flash code.
For error unlock the air heater has to be switched off
momentarily (at least 2 seconds) to be switched on
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3 Functional Description Air Top 2000